Extendable apparatus



y 31, 1966 N. E. LAUTERBACH 3,253,817

EXTENDABLE APPARATUS Filed Nov. 29, 1963 2 Sheets-Sheet l I I l INVENTOR. 28 54 46 2 NORMAN E. LAUTERBACH BYZ a ATTORNEYS May 31, 1966 N. E. LAUTERBACH EXTENDABLE APPARATUS 2 Sheets-Sheet 2 Filed Nov. 29, 1965 FIG. 4

INVENTOR. NORMAN E. LAUTERBACH ATTORNEYS 3,253,817 EXTENDABLE APPARATUS Norman E. Lauterbach, Pittsford, N.Y., assignor to Ritter Corporation, a corporation of Delaware Filed Nov. 29, 1963, Ser. No. 326,703 9 Claims. (Cl. 254-122) This invention relates to an extendable device and more specifically to an elevating mechanism suitable for medical apparatus.

One of the problems involved in medical apparatus such as surgical tables and dental chairs is elevation of the apparatus along a substantially vertical axis. There are many known devices providing this function; However it is the purpose of this invention to provide a new, novel and improved extendable elevating device which is simple and inexpensive in construction, but satisfactory for straight line vertical extendability.

Basically, I provide a plurality of links comprising two pairs of links or arms pivotally connected between a base member and a top member, the latter of which may.

comprise, for example, a section of a surgical table or constitute the seat portion'for a dental chair. The two pairs of links being pivotally interconnected at their outer ends whereby pivotal movement of the links between collapsed and extended positions moves the top member in substantially a straight line along a center vertical axis substantially perpendicular to both the base and top member.

Therefore, it is one object of my invention to provide an improved extendable device.

It is a further object of my invention to provide an improved extendable device of rugged construction.

It is another object of my invention to provide an improved extendable device requiring minimal lateral space or width per extendable length.

It is a significant object of my invention to provide a self enclosed linkage particularly suitable for use as an extendable medical device.

Other objects and advantages of this invention will be particularly set forth in the claims and will be apparent from the following description, when taken in connection with the accompanying drawings, in which:

FIG. 1 is a side-elevational view with parts broken away of one embodiment of my invention in a collapsed position;

FIG. 2 is a side elevational view with parts broken away of the FIG. 1 embodiment in the extended position;

FIG. 3 is a schematic side elevational view of the FIG. 1 embodiment of my invention;

FIG. 4 is an enlarged partial sectional view taken along lines 44 of FIG. 1 looking in the direction indicated by the 'arrows and with parts broken away; and

FIG. 5 is an enlarged sectional view generally taken along line 55 of FIG. 1 looking in the direction indicated by the arrows.

In order to more easily understand my invention, I first refer to FIG. 3 in which I have schematically illustrated the pivotal connections of the two pairs of links of the illustrated embodiment of my invention. I provide a base member and a top member 12 to each of which is pivotally connected a pair of laterally spaced links. Upper links or arms 14 and 16 are pivotally mounted at their inner ends at 18, and 20, respectively, to the top member 12 while the lower pair of links or arms 22 and 24 are pivotally connected at their inner ends 26 and 28 respectively to the base member 10.

I have shown a center axis 30 positioned centrally of the base member 10 and top member 12, spaced substantially midway between the pivot points 18, 20 and 26, 28 and the axis extends substantially vertically and perpendicular to both of the members 10 and 12. The linkage 3,253,817 Patented May 31, 1966 ice 14, 16, 22 and 24 is pivotally interconnected on one side only of the center axis 30. In the claims, the axis 30 is referred to as the center axis of extension. I am able to move the top member '12 in asubstantially straight line vertically along the center axis 30 as the top member 12 is moved, from the collapsed position illustrated in FIG. 1 to the extended position illustrated in FIGS. 2 and 3, by

pivotally interconnecting substantially the outer ends of mediate their ends at a pivot point 32; a second pair of Y opposing short links 16 and 24 are pivotally connected at their outer ends of diagonally opposing ones of the long links 22 and 14 respectively at pivot points 34 and 36.

It will be observed from FIG. 3 that the linkage between the pivot points 18, 20, 34, 32 and the linkage between the pivot points 32, 36, 28, 26 each define a trapezium in the extended position. At one position intermediate the extended position illustrated in FIGS. 2 and 3 and the collapsed position of FIG. 1, each of these linkages defines a trapezoid. Thus, my extendable linkage defines a pair of substantially symmetrical trapeziums, one being inverted with respect to the other and having a common pivotal connection 32 at a vertex formed on one side by the longest side of each trapezium. In the illustrated embodiment, the common pivotal connection 32 is equally spaced from each of the pivotal connections 18 and 26; the pivotal connections 34 and 36 are equally spaced from the common pivotal connection 32 and equally spaced from each of the pivotal connections 2t) and 28.

With reference to FIGS. 1, 2, 4 and 5, I have designated corresponding links and pivotal connections by the same numerals as is diagrammatically illustrated in FIG. 3. The function is-the same as that shown and described with respect to FIG, 3; however, for rigid construction, each of the links 14, 16, 22 and 24 are preferably of channel-shaped cross section, as for example, with reference specifically to short link 16, like the other three links, has a pair of parallel sidewalls 38 (see FIGS. 2 and 5) and an upper connecting wall 39 extending between and connecting the sidewalls 38. Diagonally opposing long link 22 also has an upper connecting wall 40, whereas long link 14 and diagonally opposing short link 24 each have lower connecting walls 41 and 43 respectively. Link 14 has an upper connecting wall 45 thereby providing a fully enclosed linkage when in the extended (FIG. 2) position and all intermediate positions.

Long link 14 and diagonally opposing short link 24 are constructed to telescope respectively within short link 16 and diagonally opposing long link 22. The sidewalls 38 of short link 16 is provided with outwardly projecting fender portions 42 into which diagonally opposing long link 22 telescopes. -In this manner, I provide an elevating device which is self enclosing thereby rendering it particularly well suited for use in the medical field. The self enclosed linkage is easily cleaned outside and serves as a shield preventing accumulation of dust inside. The telescoping links are arranged with links 16 and 22 conveniently shedding fluids, thereby rendering my invention particularly well suited for use with surgical apparatus. Also, this construction is desirable forenclosing conduits, hoses and the like extending between the base 10 and top 12.

It will be understood that the links may be pivotally connected at the pivotal points 18, 2t), 26, 28, 32, 34, and 36 as for example, by rivets, bolts or the like.

I provide a block 44 rigidly mounted to the base member 10 through which pivotal connections 26 and 28 are made. Block 44 has vertical extending shouldered portions 46 on opposite sides thereof to facilitate telescoping of short link 24 within long link 22. On the lower surface of top member 12, I provide a block 48 rigidly mounted thereon and being embraced by long link 14 through which the pivotal connection 18 is made. A pair of blocks 50 rigidly mounted on the lower surface of the top member 12 embraces the channel-shaped short link 16 on opposite sides; pivotal connections 24 are made through this pair of blocks.

The opposing pair of short links .land 24 each have a stop surface 52 and 54 (FIG. 1) respectively, adapted to engage the top member 12 and base member 10' respectively, in the extended or elevated position shown in FIG. 2 thereby limiting the elevation or extension to which the links may be pivoted. In the absence of such stop surfaces, the continued pivoting beyond the extreme extended position illustrated in FIG. 2 would, in the illustrated embodiment, result in an arcuate movement of the top member 12 with respect to the base member 10. It will be understood that variat-ions'in the relative lengths of the links and spacing between pivotal connections may be provided in order to get the desired amount of extension.

Each of the opposing long links 14 and 22 are provided with stop surfaces 56 and 58 respectively for engaging the top member 12 and base member 10 respectively in the collapsed position illustrated in -FIG. 1 thereby limiting the extent to which this device may be collapsed.

Between the upper and lower limits defined by the stop surfaces 52, 54, 56, and 58, pivotal movement of links results in straight line vertical movement of the top 12 relative to the base 10.

In order to actuate this device and pivot the links above described, I provide a motor 60 rigidly mounted by bolts 61 to a'hinge 62 which in turn is rigidly mounted on block 44, thereby providing a pivotal connection between motor 60 and block 44. Motor 60 drives a screw 64 threadedly received in a cylindrical worm nut 66 (see FIGS. 4 and having a reduced cylindrical portion 68 pivotally journalled in the sidewalls of channel-shaped short link 24. Thus, I provide an actuating mechanism which is pivotally mounted to the base member 10, thereby permitting pivotal movement of the motor 60 as the device above described is elevated or extended or collapsed. It will be understood that actuation of my device may be provided hydraulically or by other power means.

This device gives a greater amplitude of extension per horizontal side width of the device looking at it as viewed in FIGS. l3 inclusive. The channel-shaped configuration of the links provides a rigid, more rugged construction for the linkage.

While I have shown and described the preferred form of mechanism of my invention it will be apparent that various modifications and changes may be made therein, particularly in the form and relation of parts, without departing from the spirit of my invention as set forth in the appended claims.

I claim:

1. An extendable device comprising: a pair of mem-' 'links having stop surfaces adapted to engage the memher to which said one pair are connected for limiting the movement of said members between collapsed and extended positions.

2. An extendable device comprising: a pair of members, two pairs of links, each pair of links being pivotally mounted at their inner ends in spaced relationship on each of said members, and means pivotally interconnecting all of said links at substantially their outer ends at one side only of a center axis of extension extending substantially perpendicular to both of said members for linearly moving one of said members relative to the other of said members in substantially a straight line along said axis responsive to pivotal movement of said links at their inner ends and maintains said pair of members in substantially parallel relation during movement, at least two of said links having stop surfaces adapted to engage the member to which it is connected for limiting the movement of said members between collapsed and extended positions.

3. An extendable device comprising: a pair of oppos ing members, a pair of long opposing links each being pivotally connected at its inner end to one of said members, said links being pivotally connected together intermediate their ends, a pair of short opposing links each being pivotally connected at its inner end to one of said members in spaced relationship to a corresponding one of said long links, each of said pair of short links being 'pivotally connected at its outer end respectively to an of said long links having stop surfaces adapted to engage the member to which it is connected for limiting the movement of said members between collapsed and extended positions.

4. An extendable device comprising: a pair of opposing members, a first pair of channel-shaped opposing links each being pivotally connected at their inner ends to one of said members, said links being pivotally connected together intermediate their ends, a second pair of channel-shaped opposing links each being pivotally connected at its inner end to one of said members in spaced relationship to a corresponding one of said first links and each of said second pair of channel-shaped links being pivotally connected at its outer end respectively to the outer end of a diagonally opposing one of said first pair of channel-shaped links, said pivotal connections being spaced whereby movement of said links between collapsed and extended positions moves one of said members in a substantially straight line perpendicular to said one member and maintains said pair of members in substantially parallel relation during movement, each of said links having parallel sidewalls and connecting sidewalls defining the channel shape of the links, the sidewalls of all links being constructed to coactively provide a self-enclosed linkage when moving between collapsed and extended positions.

5. An extendable device comprising: a pair of opposing members, a pair of long channel-shaped opposing links each being pivotally connected at its inner end to one of said members, said links being pivotally connected together intermediate their ends, a pair of short channelshaped opposing links each being pivotally connected at its inner end to one of said members in spaced relationship to a corresponding one of said long links and each of said pair of short channel-shaped links being pivotally connected at its outer end respectively to the outer end of a diagonally opposing one of said pair of long channel shaped links, said pivotal connections being spaced whereby movement of said links between collapsed and extended positions moves one of said members in a substantially straight line substantially perpendicular to said one member and maintains said pair of members in substantially parallel relation during movement, each of said links having parallel sidewalls and connecting sidewalls defining the channel shape of the links, the sidewalls of all links being constructed to coactively provide a selfenclosed linkage when moving between collapsed and extended positions.

6. An extendable device comprising: a pair of opposing members, a pair of long opposing links each being pivotally connected at its inner end to one of said members, said links being pivotally connected together intermediate their ends, a pair of short opposing links each being pivotally connected at its inner end to one of said members in spaced relationship to a corresponding one of said long links, each of said pair of short links being pivotally connected at its outer end respectively to an outer end of a diagonally opposing one of said pair of long links, and all of said pivotal connections being coactively arranged whereby pivotal movement of said links between collapsed and extended positions moves one of said members in substantially a straight line and mai11- tains said pair of members in substantially parallel relation during movement, all of said links have stop surfaces adapted to engage the member to which it is pivotally connected at its'inner end, said long link stop surfaces limiting the movement of said links when being collapsed and said short link stop surfaces limiting the movement of said links when being extended.

7. An extendable device comprising: a pair of opposing members, a pair of long channel-shaped opposing links each being pivotally connected at its inner end to one of said members, said links being pivotally connected together intermediate their ends, a pair of short channelshaped opposing links each being pivotally connected at its inner end to one of said members in spaced relationship to a corresponding one of said long links and each of said pair of short channel-shaped links being pivotally connected at its outer end respectively to the outer end of a diagonally opposing one of said pair of long channelshaped links, said pivotal connections being spaced whereby movement of said links between collapsed and extended positions moves one of said members in a substantially straight line substantially perpendicular to said one member and maintains said pair of members in substantially parallel relation during movement, each of the long and short channel members connected to a common member telescoping relative to each other, each of said links having parallel sidewalls and connecting sidewalls defining the channel shape of the links, the sidewalls of all links being constructed to coactively provide a selfenclosed linkage when moving between collapsed and extended positions.

8. An extendable device comprising: a pair of opposing top and base members, a pair of long channel-shaped opposing links each being pivotally connected at its inner end to one of said members, said links being pivotally connected together intermediate their ends, a pair of short channel-shaped opposing links each being pivotally connected at its inner end to one of said members in spaced relationship to a corresponding one of said long links and each of said pair of short channel-shaped links being pivotally connected at its outer end respectively to the outer end of a diagonally opposing one of said pair of long channel-shaped links, said pivotal connections being spaced whereby movement of said links between collapsed and extended positions moves one of said members in a substantially straight line substantially perpendicular to said one member, and maintains said pair of members in substantially parallel relation during movement, the long link connected to the top member telescoping within the short link connected to the top member, each of said links having parallel sidewalls and connecting sidewalls defining the channel shape of the links, the sidewalls of all links being constructed to coactively provide a self-enclosed linkage when moving between collapsed and extended positions.

9. An extendable device comprising: a pair of opposing top and base members, a pair of long'channel-shaped opposing links each being pivotally connected at its inner end to one of said members, said links being pivotally connected together intermediate their ends, a pair of short channel-shaped opposing links each being pivotally connected'at its inner end to one of said members in spaced relationship to a corresponding one of said long links and each of said pair of short channel-shaped links being pivotally connected at its outer end respectively to the outer end of diagonally opposing one of said pair of long channel-shaped links, said pivotal connections being spaced whereby movement of said links between collapsed and extended positions moves one of said members in a substantially straight line substantially perpendicular to said one member, and maintains said pair of members in substantially parallel relation during movement, the long link connected to the top member telescoping within the short link connected to the top member and the short link connected to the base member telescoping With the long link connected to the base member, each of said links having parallel sidewalls and connecting sidewalls defining the channel shape of the links, the sidewalls of all links being constructed to coactively provide a selfenclosed linkage when moving between collapsed and extended positions.

References Cited by the Examiner UNITED STATES PATENTS 12/ 1946 Kuehlman et al.

8/1956 Pickard et al. 254-126 

1. AN EXTENDABLE DEVICE COMPRISING: A PAIR OF MEMBERS, TWO PAIRS OFLINKS, EACH PAIR OF LINKS BEING PIVOTALLY MOUNTED IN SPACED RELATIONSHIP AT THEIR INNER ENDS TO EACH OF SAID MEMBERS, SAID LINKS BEING PIVOTALLY INTERCONNECTED AT THEIR OUTER ENDS AT ONE SIDE ONLY OF A CENTER AXIS OF EXTENSION WHEREBY PIVOTAL MOVEMENT OF SAID LINKS BETWEEN COLLAPSED AND EXTENDED POSITIONS MOVES ONE OF SAID MEMBERS IN SUBSTANTIALLY A STRAIGHT LINE ALONG SAID AXIS AND MAINTAINS SAID PAIR OF MEMBERS IN SUBSTANTIALLY PARALLEL RELATION DURING MOVEMENT, AT LEAST ONE PAIR OF SAID LINKS HAVING STOP SURFACES ADAPTED TO ENGAGE THE MEMBER TO WHICH SAID ONE PAIR ARE CONNECTED FOR LIMITING THE MOVEMENT OF SAID MEMBERS BETWEEN THE COLLAPSED AND EXTENDED POSITIONS. 